The purpose of this study is to see if CC100, given by mouth, is safe and is tolerated in increasing doses. How long the drug remains in the body will also be calculated.

Approximately 18 healthy subjects will be randomized to receive by mouth either 3 single increasing doses of CC100 or 1 dose of placebo and 2 increasing doses of CC100. Dosing will occur every 2 to 7 days for a study duration of 5 to 15 days from the 1st dose. Subjects are required to stay in the Clinic for approximately 24 hours following each dose. Subjects may choose to have an optional lumbar puncture following the 3rd dose of study drug.

Inclusion Criteria:

• Men must practice a reliable method of birth control during study and for 2 weeks following study. Women must be non-fertile or post-menopausal.

Exclusion Criteria:

• Have serious or unstable illnesses as determined by the investigator.
• Have current or a history of asthma, or severe drug allergies or pollen allergy.
• Have used medications (except for calcium supplements or externally applied eye drops or antibiotics) within 30 days prior to dosing or are expected to use other medications during the study.
• Have had serious infectious disease affecting the brain within the preceding 5 years; or have known or existing evidence of serious infection.
• Have laboratory test values that are considered clinically significant as determined by the investigator.
• Have ECG abnormalities that are clinically significant.
• Have donated blood (a pint or more) or received an experimental drug within 30 days prior to dosing.
• Have a history of chronic alcohol or drug abuse within the past 2 years.